Britain is set to tackle a 60-year-old problem that has dogged successive governments: how to resolve the deadly legacy from the country's first generation of nuclear power plants.
The UK is home to the world's largest stockpile of plutonium, with more than 100 tonnes of the highly radioactive material.
The Nuclear Decommissioning Authority, whose job it is to look after the plutonium, is preparing to give its recommendation on how the government should deal with the problem, with an announcement expected as early as next month.
In the early days of the UK's civil nuclear programme some forecast that uranium - used to fuel conventional reactors - would rapidly run out. The UK decided to stockpile plutonium - which is extracted from reprocessed nuclear waste - as an alternative to be used in a new generation of experimental reactors.
However, not only were the forecasts about uranium wrong but the reactors were never built.
Storing the plutonium has become an expensive business whose bill is picked up by the taxpayer. While the material can be used to fuel nuclear reactors, some of the technologies are unproven, and plutonium's toxicity makes prolonged storage risky.
The government has previously said its preferred option is to convert the plutonium into so-called mixed oxide fuel, or Mox, for use in new reactors.
However, the NDA has also been considering two alternative proposals from nuclear technology groups, GE Hitachi, the US-Japanese joint venture, and Canada's Candu.
"We have some market tension going," says Adrian Simper, the NDA's strategy and technology director, adding that the intention is to recommend whether "there are three options, two or one - or even none".
All three carry their own risk - and cost. If the government decides to turn the plutonium into Mox it would require hefty investment in the form of a plant to make the material. The cost depends on a variety of factors, including how much is produced.
To convert 40-60 tonnes a year would require an estimated capital cost of £1bn-£2bn, according to Areva, the nuclear technology group that has been turning spent fuel from reactors into Mox for several decades in its native France. Other estimates have suggested a new plant could cost double that amount.
"We are open about what kind of role we can play," Dominique Mockly, head of used nuclear fuel and related services at Areva, says of the company's interest in the UK. "The solution is easy to implement as it is industrially viable," he added.
Britain has tried Mox before. A previous plant built at Sellafield in the 1990s was dogged by technical problems and produced a minimal amount of fuel. It was closed in 2011 after the accident at Japan's Fukushima plant.
The second option is to use the EC-6 reactor built by Candu, which can burn different types of elements, including natural uranium and Mox fuel. This would also require the building of a Mox plant, and the design would still need to be licensed in Britain.
Under the third proposal, from GE Hitachi, the plutonium would be burnt in one of its fast breeder Prism reactors. They burn plutonium to produce electricity and the by-products can be used for other types of nuclear power stations.
While critics have said the technology is not mature enough, GE Hitachi has promised to build the twin reactors without any public subsidies and charge only for the amount of plutonium processed.
"This is not pie in the sky," said a spokesman for GE Hitachi, adding that the reactor is "a combination of proven tools used in a new combination".
Whichever options the NDA recommends, it is likely to take another couple of years before the government decides on a final route. Says the NDA's Mr Simper: "This is a marathon, not a sprint."
Sellafield stockpile
Britain's nuclear legacy will forever be tied up with Sellafield. The one-and-a-half square mile site, originally home to a second world war munitions factory, became the country's first nuclear complex in the 1940s. Its Calder Hall reactors, the world's first commercial atomic plants, began generating electricity in the mid-1950s.
Today, the site is home to the bulk of Britain's plutonium stockpile, as well as a variety of decommissioning and other waste management activities. The cost of cleaning up Sellafield's hazardous radioactive waste is estimated to be a staggering £67.5bn. A report by the Commons public accounts committee earlier this year questioned the wider benefits of the £1.6bn a year spent at Sellafield and suggested private contractors were taking on little risk.
The Nuclear Decommissioning Authority, which owns all of the UK's civil nuclear sites, will decide later this year whether to extend a management contract of Sellafield with current operator Nuclear Management Partners, a consortium made up of URS, Amec and Areva. The NDA has pledged to take value for money into account when making its decision.